Open up the PDC (Power Distribution Center) access panel and using the layout diagram contained on the lid, find the Starter relay. Once you have found it, put your ear next to it and listen for a soft click inside the relay as a helper turns the ignition key to Start. If it doesn't click, odds are the relay itself is bad or the ignition switch is bad. You can swap that starter relay with one of several other similar size relays in the PDC, most are the same type relay. I think the horn relay is the same so can swap the relays between those two to see if that helps.
Or if the starter relay does click, that means either the wiring between it and the starter solenoid is bad, or the starter solenoid is bad. A test light can confirm whether the starter solenoid is getting voltage or not from the starter relay.